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Science / Space Race

[June 28, 1968] Classified Communications (IDCSP Satellite Constellation)

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by Kaye Dee

An advantage of previously working for the Weapons Research Establishment in South Australia is that I am still able to get information (of the unclassified variety, of course) about defence space programmes from my former colleagues. This is particularly helpful when I’m writing about space projects that are not getting a large amount of press coverage here in Australia.


One such project is the Initial Defence Communication Satellite Programme (IDCSP), the United States’ first global military communications network. The most recent IDCSP launch took place on 13 June with the launch of eight satellites on a Titan IIIC rocket, bringing the total number of satellites in the constellation to 27.

The Advent of Defence Satellite Communications
The very first experimental communications satellites were created by the U.S. armed forces. Project SCORE was jointly developed by the U.S. Air Force and communications company RCA, while the first active repeater comsat, Courier 1-B, was developed by the U.S. Army Signal Corps. I think we can be sure that these early satellites satisfactorily carried out classified experiments in secure defence communications, as the first planned military satellite communications network, Project ADVENT, commenced development in February 1960.

Diagram of the proposed ADVENT satellite in orbit

ADVENT intended to place several large, three-axis stabilised, heavy satellites in geosynchronous orbit (with one of its ground stations planned to be located in the Australian Trust Territory of Papua New Guinea). However, this extremely ambitious programme soon fell behind schedule and saw costs balloon out to twice the original estimates, leading to its cancellation in 1962. It’s perhaps not surprising that the ADVENT programme faced difficulties in developing its satellites – even six years later, an operational three-axis stabilised satellite has yet to become reality.

The engineering test vehicle for the ADVENT satellites under construction

Enter IDCSP
Following ADVENT’s cancellation, the U.S. Air Force embarked on a new satellite communications system as a replacement. Originally called the Interim Defence Communications Satellite Programme, it has since been renamed as the Initial Defence Communications Satellite Programme. IDCSP is intended to be the first stage in the longer-term Defence Communications Satellite Program (DCSP), which is being managed by the Defence Communications Agency.

Commenced in 1962, the IDCSP is designed to be significantly cheaper than ADVENT by using a constellation of small, much simpler satellites. The original plan was for a constellation of 24-30 satellites, placed into Medium Earth Orbit using ten Atlas Agena rockets. In October 1963, the programme was placed on hold while the Pentagon investigated renting satellite communications capability through the INTELSAT system, but this idea was abandoned in mid-1964 and Air Force resumed work on the IDCSP.

Doing the Heavy Lifting
As it happened, the delay worked to the IDCSP’s advantage. By 1964, the development of the U.S.A.F.’s heavy-lift Titan IIIC offered the possibility of lofting up to eight satellites per launch. This has meant that the total number of launches required to establish the constellation, and thus the overall cost of the programme, has been greatly reduced. It seems that the Pentagon decided to negotiate “free rides” on early Titan IIIC development launches, although this earned some censure from Congress for risking the success of the programme with launches on an unproven vehicle just to keep costs down! Fortunately, it has been a risk that has largely paid off.

The Air Force decided to develop the Titan III family so that it would have a heavy launch capability independent of NASA’s Saturn rockets. The Titan III vehicles are derived from the Titan II I.C.B.M., that was also the basis of the Titan launch vehicle used for NASA’s Gemini programme. The core of the Titan IIIC is a modified two-stage Titan II, structurally strengthened to accommodate heavier payloads and additional stages. The launcher has two strap-on solid rocket boosters and an additional upper stage with engines that can be restarted, known as the Transtage.

The 25 ft long Transtage uses a pair of Aerojet AJ10-138 engines that are similar in design to the larger engine that Aerojet is developing for the Apollo Service Module. These engines enable the Transtage to put heavier payloads into much higher orbits than the Atlas Agena rocket originally selected for IDCSP. This means that it can place as many as eight IDCSP satellites at a time into sub-synchronous orbits (more on that below) of around 21,000 miles.

The complex requirements for the preparation and launch of a Titan III and its payloads has necessitated the construction of a totally new facility at Cape Kennedy, with three pads, designated Launch Complexes 40, 41 and 42 (this last not yet built). There is also a new Vertical Integration Building (VIB), which can support the simultaneous assembly of up to four Titan III core vehicles. It also contains the Titan III launch control centre.

Keep it Simple
The IDCSP satellites have been designed to avoid the development delays that come from being too technologically ambitious – the kind that sealed the fate of ADVENT. Every satellite in the constellation is an identical spin-stabilized, 26-sided polygon, 34in in diameter. The 100lb satellites are covered with solar cells and have been deliberately kept technologically very simple: they have no back-up batteries or on-orbit command systems. Without command systems, they are virtually “jam-proof” and cannot be moved off orbit by false commands sent by an enemy.

Each satellite has a single 3.5W X-band transponder with a 26 MHz bandwidth. It can handle 600 voice channels or 6000 teletype signals. While the designers have planned for these initial satellites to be operational for three years, they are equipped with an automatic “kill switch”, which is intended to deactivate them after six years in orbit, so that they will not produce any signals that would interfere with more advanced future replacement satellites.

As the small satellite’s transponders are low powered and use a low-gain antenna, the present ground stations are comparatively large, but there are plans for future, smaller mobile ground stations.

“Sprinkled Across the Sky”
One of the few local newspaper articles that I saw about the launch of the first batch of IDCSP satellites described them rather poetically as being “sprinkled across the sky” when they were first released into orbit from the Titan IIIC Transtage. Six hours after launch, the deployment truss on which the IDCSP satellites are mounted enables the satellites to be dispersed one-by-one into orbit, over about 3 minutes. As they are released, the satellites drift apart as they move into orbit.

Because they are not quite in geosynchronous orbit (orbiting at the same speed the Earth rotates, which would "fix" them in the sky), the satellites drift randomly at approximately 28° per day, over time forming a ring of satellites approximately evenly spaced above the Earth's equator. This sub-synchronous orbit has the advantage that the failure of one satellite would not leave a major gap in coverage; at least one other satellite of the constellation would always be visible to an Earth station if one failed. 12 satellites were considered the minimum necessary to provide full coverage, so the current constellation has plenty of redundancy even if several satellites fail. The daily movement of the satellites makes them difficult to track, which also helps to make them more secure against enemy interference.


What are they for? Ssshhh, it’s Secret!
The IDCSP constellation is designed to provide the U.S. military with swift, jam-resistant radio links to its forces in South Vietnam and elsewhere around the world in times of crisis. The satellites enable 24 hour-a-day contact between the Defence Department in Washington and forces in the field. While the IDCSP programme is publicly acknowledged, the satellites are reserved for secret and sensitive command-and-control communications. Routine administrative and logistical messages are relayed by INTELSAT satellites.

IDCSP ground terminals have been installed at American bases at Saigon and Nha Trang, and rumour has it that there have already been experiments with sending high-resolution photographs from Saigon to the Pentagon via satellite, enabling rapid battlefield analysis. In addition to the two ground stations in South Vietnam, there are six other IDCSP ground stations, including in the U.S. and Britain.

Building the IDCSP Satellite Network
The first batch of seven IDCSP satellites was launched from Florida on 16 June 1966, as the payload of the fourth Titan IIIC. In addition to the communication satellites, an eighth satellite, structurally based on the IDCSP satellites and designed to test an experimental gravity gradient stabilisation technique, was also flown. Communications tests were carried out between ground stations in New Jersey, California, England and Germany.

Unfortunately, the second set of eight IDCSP satellites was lost on 26 August 1966 due to the failure of the fifth Titan IIIC’s payload fairing. A replacement set of eight satellites was sent into orbit on the seventh Titan IIIC, on 18 January 1967, followed on 1 July by a further four IDCSP satellites. IDCSP 19 was another experimental satellite, also known as DATS (Despun Antenna Test Satellite), designed to test a more efficient electronically despun antenna platform.

The most recent launch, on 13 June, has come almost exactly two years after the first satellites in the network were put into orbit. Its eight satellites are the final ones to be added to the system, which is now considered to be “operational”, rather than “experimental”.

Britain Follows Suit
Britain has taken an interest in the operation and performance of the IDCSP satellites, as it intends to launch its own military communications satellite soon, to provide military communications across the British Commonwealth. Skynet has been in planning since 1962, with the U.K. deciding on an initial satellite in geostationary orbit over the Indian Ocean, to support force deployments east of Suez. Skynet is considered to be more advanced than IDCSP, as it will have a transponder with two channels, allowing communications between two types of ground station.

Model of a Skynet 1 satellite

Britain was invited to participate in IDCSP in 1965, and the Marconi company built a ground station at its facility in Christchurch, Hampshire, to conduct experiments with the first batch of IDCSP satellites when the U.S. was not using them. Nine ground stations have been planned for Skynet, which are also able to communicate with the IDCSP satellites. These stations will be able to send secret military communications to a large number of locations within the British Commonwealth.

The U.S. Philco Ford company, which developed the original IDCSP design, was contracted to build the first-generation Skynet 1 satellites (of which there will be two). The Marconi company is assisting with this work so that the U.K. will develop the expertise needed to build the Skynet 2 series satellites. Unlike the IDCSP constellation, Skynet satellites will have an on-board manoeuvring system so that they can be kept on station, or moved from one location or another.

With the United States and Britain developing defence communications satellite systems, it's virtually certain the USSR will be doing the same – if it does not have an operational network already (perhaps some of those mysterious Kosmos satellites whose purpose in orbit is unknown?) Since reliable communications are vital to any military operation, it's not hard to imagine that defence comsats like IDCSP and Skynet could become the first casualties in any future superpower conflict…








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Science / Space Race

[June 28, 1967] Around the World in Two Seconds (Our World Global Satellite Broadcast)

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by Kaye Dee

I love how our world is drawing closer every day to some of the amazing futures that science fiction has spread before us. I’ve written before about the importance of satellite communications in connecting this divided planet. Just two days ago, 24 countries around the globe were linked together in the first world-spanning live satellite broadcast, titled – appropriately enough – Our World.

Our World's visual symbol incorporates a modernised version of da Vinci's "Vitruvian Man", with arms encircling the globe, and vertical and horizontal lines representing longitude and latitude

Down Under Comes Up Live – from a town with no television!
For us in Australia, being instantaneously connected to the rest of the world through phone and television is a major step in breaking the “tyranny of distance” that has shaped our national history. Our first Satellite Earth Station was opened just last October in Carnarvon, a remote township in Western Australia, whose only other connection to the rest of the world is a phone line. It’s no wonder NASA wanted to provide a satellite connection back to the United States for its tracking station located there, using the INTELSAT communications network. Just after the station opened, a mishap with the launch of the first INTELSAT II satellite (Blue Bird) on 26 October placed the satellite into the wrong orbit, providing an opportunity for the first satellite broadcast from Down Under.


SES Carnarvon's unusual antenna, one of only four that have been built for the INTELSAT network. Officially described a 42-foot aperture cassegrain-fed folded-horn antenna, you can see why it's nicknamed the “sugar scoop”

According to my friend at the Australian Broadcasting Commission (ABC), some hasty calculations revealed that short segments of television broadcast could be relayed to the United Kingdom via INTELSAT II in its unplanned elliptical orbit. So the ABC and the BBC quickly put together a plan for a live telecast, called Down Under Comes Up Live, from Carnarvon – a town which doesn’t even have a television service!

Connection was the theme, and ordinary people were the stars of the show. The program reunited three families of British immigrants living in Carnarvon, two of whom who happened to be employees of the NASA tracking station, with their relatives in the BBC studios in London. It also included some interviews with local residents talking abut life in their remote community. Introducing new babies to family is a universal ritual, and it's delightful to see that it was one that played out in both Down Under Comes Up Live and Our World.

Down Under Comes Up Live was a direct one-way broadcast (a return signal was not possible for technical reasons) that was a complex undertaking (and a good rehearsal for our involvement in Our World). Without a local television station in Carnarvon, ABC outside broadcast vans and their technical staff made a 560 mile trip from Perth to produce the program. The vision was sent live to London from the satellite station, but the audio to and from London was transmitted separately by cable.

On Friday 25 November 1966, more than twelve minutes of television was broadcast to London. Although the program was seen live in the UK, rather ironically, we couldn’t see it live in Australia because there are no television links between Carnarvon and Perth. We had to wait for a few days to see this history-making program, once a film copy of the UK broadcast was flown back to Australia.

Incoming – Australia Day at Expo 67
Apart from a few test transmissions, it was just three weeks ago that we saw the first satellite broadcast into Australia – a live telecast of Australia’s ‘special day’ at Expo 67 in Montreal. This time the transmission came via NASA’s Applications Technology Satellite (ATS)-1. To support this program, NASA has established a temporary satellite station at Cooby Creek dam, about 14 miles north of Toowoomba in Queensland.

The picturesque setting for NASA's Cooby Creek tracking station that brought both Australia Day at Expo 67 and Our World to Australia via ATS-1

Several hundred thousand people around the country, including my sister’s family and I, watched live through the early hours of 7 June our time, as Australia took centre stage in Canada. The program commenced with Prime Minister Harold Holt officially opening the Australian Pavilion at the Expo. Special events for “Australia Day” included boomerang throwing, sheep-dog trials, wood chopping contests and tennis matches with members of the Australian Davis Cup team. Celebrity was an important theme for the variety concert, "Pop Goes Australia", which showcased Australian talent, including the internationally-known Rolf Harris and The Seekers.

The clarity of the satellite picture from Montreal was surprisingly good: I’ve heard that hundreds of viewers rang the ABC in Sydney wanting to be assured that the vision really was being broadcast live from Canada! I just wish I could find some decent reproductions to show you or had thought to take a picture on the screen of our TV set. 

Our World – joining hands (almost) around the planet
So, with just two satellite broadcasts under its belt, from 4.50am Australian Eastern Time on 26 June, Australia participated in the Our World program, helping to string Puck's "girdle around the world". We joined 13 other nations in providing television content for the first live global television broadcast, which instantaneously linked 24 countries on six continents via four communications satellites, with the signals travelling around the world in just 2 seconds!

The brainchild of the BBC, though produced under the auspices of the European Broadcasting Union, the global telecast was controlled from the BBC in London, with America’s National Educational Television in New York City feeding items from the United States, Canada, Mexico, Australia and Japan to the British Control Centre. Literally thousands of technicians handled the outside broadcasts and studio operations around the world. Satellite ground stations in Australia (NASA's Cooby Creek facility again), Japan, Canada, the United States, Britain and France transmitted sound and vision to and from the satellites. As each of the contributing countries provided commentary in their own language, there was also the necessity of rapidly translating the various languages, so that everyone in the receiving countries could understand what was being said.

The technical complexity of Our World is evident from this diagram, which shows just part of the world-wide links between television stations and satellites necessary to make the global broadcast a reality

Given the incredible technical complexity of the television transmission, it’s quite amazing that the two-hour program was carried through with very few technical problems – especially when the entire broadcast was televised live, with no filmed insertions or other previously produced material apart from the opening montage. We saw everything as it happened.

Our World was intended as a major achievement for both space technology and international relations, a bridge between East and West in these troubled times of wars cold and hot. Unfortunately, at the last minute, politics reared its ugly head and the USSR and several Eastern European nations that were originally going to participate pulled out of the broadcast just a few days before, as a protest against the recent war in the Middle East. This was disappointing and made for some hurried re-arrangement of parts of the program, but it didn’t dampen the mostly aspirational tone of the broadcast as a celebration of human achievement and hope for a more peaceful future. There was also the irony that a US segment about the Glassboro, New Jersey conference between American president Lyndon Johnson and Soviet premier Alexei Kosygin was still included in the broadcast, although – since the Our World producers insisted that no politicians could be shown – only an external view of the house where the conference was being held was televised.

New Babies and their World
The broadcast crossed countries, seas and time zones, and was presented as fusing “yesterday”, “today” and “tomorrow” (by dint of the different time zones around the world) into a globe-encircling “now”. The birth of several babies across the world opened the program, which was presented in a sense as a “survey” of the world into which these newborns are entering.

A baby in Mexico, born live on television for all the world to see!

The babies are introduced to their new world through several themes: This Moment's World (what people were doing are doing at that moment around the world); the Hungry World (what scientists are doing to attempt to solve or alleviate the hunger problem); the Crowded World (looking at proposed solutions to the population explosion); Aspiration to Physical Excellence (the continual attempt to develop physical skill); Aspiration to Artistic Excellence (the drive to excel in the arts); and the World Beyond (focussed on astronomy and space travel. Within these themes, vignettes of life and activity from around the world formed the tapestry of the program. Even if some of the actual presentation was, quite frankly, dull and pedestrian (the excitement was, after all, the fact that we were seeing something live from another part of the globe), I thought the concept was an interesting way to approach telling the story of our planet. If an extra-terrestrial civilisation one day happens to intercept this program as its signals travel through space, they'll learn a lot more about the reality of the Earth and its people from Our World than they will get from episodes of I love Lucy.

Everyday Life

The theme This Moment's World presented a panorama of people and activities in various parts of the globe, moving through evening in Europe to afternoon in New York City, with a visit to Tunis along the way. I loved the views of old and new parts of the city. We saw Marshall McLuhan being interviewed in a Toronto television control room, people swimming at the beach at lunchtime in Vancouver, Canada (making us Aussies all envious on a cold winter's morning) and workmen digging a subway at 4am in Japan. Since the program took place between 5.00 am and 7.00 am Australian Eastern time, our first contribution commenced at 5:22 am local time, with a visit to the Hammer Street Tram Depot in Melbourne, where the first tram of the day was departing to service Monday morning commuters. 

This segment was the first cross to the Southern Hemisphere and came directly after the broadcast from Japan. The switch from Japan to Australia was apparently the most technically complicated of the program, as the Japanese and Australian satellite stations had to switch immediately from transmission to receiving mode and back again. The material coming into Australia also had to be converted from the 525-line system to our 625-line format for local broadcast, while the segment going out of Australia had to be converted from 625 to 525-line in order to be sent back to the US and then on to London!

Sweden gave us the first – and almost the only – female presenter in the program!

Global Concerns
Australia also featured in the Hungry World theme, which concentrated on food production and the issues of feeding an ever-growing world population. In addition to items from the United States and a shrimp farm in Takamatsu, Japan, we visited the Canberra phytotron, a laboratory run by the national scientific research agency, CSIRO. In the phytotron, plants can be grown under a wide range of closely controlled climatic conditions. It’s claimed to be one of the world's finest and most up-to-date facilities for plant research, and a number of international scientists work there alongside local researchers.

The CSIRO phytotron's Director, Dr. Lloyd Evans, at work in his plant laboratory. Apparently, he often starts his workday at 5am, so he didn't have to get up earlier than usual for the show!

A couple of segments that were of interest to me in The Crowded World theme were a visit to Cumbernauld (near my father’s home town of Glasgow, Scotland), which was the recipient of an international award for best planning in a new town, and a glimpse of Habitat, a new concept of living accommodation, on display at Expo '67.

Human Achievement
In Aspiration to Physical Excellence, there were contributions from Rome, Sweden, France (where a parachutist made a dizzying free fall with a camera strapped to him), and Winnipeg, Canada, where a 16-year-old Butterfly champion attempted to beat her own world indoor swimming record.


We get to watch live as actors rehearse the wedding scenes from Italian director Franco Zefferelli's next film, Romeo and Juliet
Aspiration to Artistic Excellence included a visit to the Maeght Foundation museum of modern art in France, with artists Marc Chagall and Joan Miro, Leonard Bernstein and pianist Van Cliburn rehearsing Rachmaninoff's Third Piano Concerto. Opera singer Maria Callas, and painter Pablo Picasso also featured. In the context of this theme, it’s interesting to note that the Our World anthem, which accompanied the opening montage was composed by Frenchman Georges Delerue, whose musical score credits includes the recent Academy Award winning motion picture, A Man for All Seasons. He wrote the melody based on the rhythm established by the words “Our World”, sung in 22 different languages by the Vienna Boys’ Choir.

But the highlight of this theme has to be a ‘fly on the wall’ visit to a recording studio where the fabulous Beatles were recording their latest anthem “All You Need is Love”, which was specially written for the Our World broadcast! You can see them below, surrounded by their many friends in the music world, who came to the recording party and became informal backing singers. The black and white shot shows how we saw the FAB Four in the live broadcast, while the colour photo was taken just before the televised performance. 

 
Reaching for the Stars
The World Beyond theme took us to the heart of the Space Race, with a visit to Cape Kennedy to see a Saturn V Moon rocket on the pad being readied for its first flight. The telecast also came to a close on the theme of outer space, with a visit to Australia’s Parkes radio telescope – at 210 ft. the largest fully-steerable radio telescope in the world. Here we sat in on an observation of the most distant object currently known – a mysterious quasar only discovered last year by the Parkes telescope's director, Dr. John Bolton. It’s so far away that its light and radio signals take 13,000 million years to reach us!

An ABC cameraman, wearing a heavy jacket in the early morning winter cold, prepares for filming the Our World segment at the Parkes Radio Telescope.

So that was Our World. A fascinating mix of banality and creativity, made magical by the technology of the Space Age, and the knowledge that everyone watching was sharing the experience simultaneously with millions of others across our planet in a way that has never before been possible. With a worldwide audience estimated between 350 and 700 million, the broadcast was a potent demonstration of the potential reach of satellite television. I'm sure that before too long, satellite television from around the world will be a regular occurrence, bringing us news, sport, entertainment and major world events – and we here in Australia will have to get used to being up at all hours of the night to watch! But I wonder what will top this broadcast's incredible audience reach? The first manned landing on the Moon, perhaps?



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Science / Space Race

America SCORES! (12-22-1958)

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Unless the Soviets can pull a rabbit out of their hat, it looks like the United States will come out the winner in the Space Race for 1958.

It was only a matter of time before we finally used our Atlas rocket, the nation's first Intercontinental Ballistic Missile (ICBM), to launch a satellite.  With the Atlas, we can finally throw up payloads of similar weights to those launched by the Soviets with their ICBM.

The first Atlas mission, Project SCORE, was launched on December 18, 1958.  It is the heaviest payload ever to be launched by the United States into orbit—a whopping 8000 pounds' worth!  That compares favorably to the 9000 pound payload launched by the Soviet Union in May (Sputnik III).  Of course, those figures are a little less impressive when one realizes that the vast bulk of that weight actually comprises the last stage of the rocket.  Moreover, Sputnik III carried over a ton of instrumentation.  SCORE carries a bare 150 pounds of payload.

What SCORE does, however, is unprecedented.  Quite simply, it is the world's first communication's satellite.

Currently, if one wishes to send a message across the country or the world, one must either use archaic transoceanic cables or, more frequently, send the signal via some sort of radio.  The former method puts strong limits on destination (messages can only go where the cables are strung), and the latter is only as reliable as the atmosphere will allow.  Reception at remote locations is virtually impossible.  But with a satellite, one truly has the high ground.  Messages can be beamed anywhere along the satellite's line of sight, which is essentially limitless. 

Developed jointly by the Air Force and veteran communications company, RCA, SCORE has the ability both to broadcast messages as they are beamed to it from ground stations and to store received messages and transmit them later.  Seeing how it was an Air Force mission, there were probably plenty of classified messages sent and re-transmitted, but the one everybody got to know about was this one, recorded by President Eisenhower the day after launch:

"This is the President of the United States speaking.  Through the marvels of scientific advance, my voice is coming to you from a satellite circling in outer space.  My message is a simple one: Through this unique means I convey to you and to all mankind, America's wish for peace on Earth and goodwill toward men everywhere."

Once again, science fiction has become fact.  Arthur C. Clarke predicted communications satellites in the '40s, and here we are at the dawn of a new era. 

If that era comes.  It must be cynically pointed out that this launch had a second purpose—to show the Soviets that we, too, have the ability to send a nuclear bomb 6,000 miles across the globe.  While this represents a technological achievement and another example of science fiction become fact, I somehow can't be as excited about this development.  It is yet another reminder that, thus far, the exploration of space has been primarily a military endeavor, and our plowshares are barely modified swords.

(Confused?  Click here for an explanation as to what's really going on)

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